Barrier filtration units are used in many industrial applications to selectively remove material from one or more fluid streams. Filter assemblies containing filtration media are used to both remove undesirable contaminates from the fluid and to extract desirable filtrates out of the fluid. Many filter assemblies include one or more filter units that are connected in parallel fashion to inlet and outlet headers through which the fluid stream is, respectively, applied to and removed from the filter units. Often these assemblies are further provided with some type of backwashing mechanism, which discharges accumulated solids from the filtration media by locally reversing flow through the filtration media.
Many filtration units have two or more filter housings to increase the filtering capacity of the system. The multiple filter housings may be arranged in a filter array connected to a common manifold with a diverter valve to control the fluid flow through each filter element. The diverter rotates or otherwise shifts position to close a selected filter housings from incoming liquid and open the filter unit to the drain circuit. As a result, the selected filter housing can undergo the backwashing cycle while the remaining filter housings continue to operate in the filtration cycle. As the diverter shifts position, individual filter housings can be cleaned without interrupting the overall filtering capacity of the filtration unit.